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+* STMicroelectronics STM32 IPCC (Inter-Processor Communication Controller)
+
+The IPCC block provides a non blocking signaling mechanism to post and
+retrieve messages in an atomic way between two processors.
+It provides the signaling for N bidirectionnal channels. The number of channels
+(N) can be read from a dedicated register.
+
+Required properties:
+- compatible: Must be "st,stm32mp1-ipcc"
+- reg: Register address range (base address and length)
+- st,proc-id: Processor id using the mailbox (0 or 1)
+- clocks: Input clock
+- interrupt-names: List of names for the interrupts described by the interrupt
+ property. Must contain the following entries:
+ - "rx"
+ - "tx"
+ - "wakeup"
+- interrupts: Interrupt specifiers for "rx channel occupied", "tx channel
+ free" and "system wakeup".
+- #mbox-cells: Number of cells required for the mailbox specifier. Must be 1.
+ The data contained in the mbox specifier of the "mboxes"
+ property in the client node is the mailbox channel index.
+
+Optional properties:
+- wakeup-source: Flag to indicate whether this device can wake up the system
+
+
+
+Example:
+ ipcc: mailbox@4c001000 {
+ compatible = "st,stm32mp1-ipcc";
+ #mbox-cells = <1>;
+ reg = <0x4c001000 0x400>;
+ st,proc-id = <0>;
+ interrupts-extended = <&intc GIC_SPI 100 IRQ_TYPE_NONE>,
+ <&intc GIC_SPI 101 IRQ_TYPE_NONE>,
+ <&aiec 62 1>;
+ interrupt-names = "rx", "tx", "wakeup";
+ clocks = <&rcc_clk IPCC>;
+ wakeup-source;
+ }
+
+Client:
+ mbox_test {
+ ...
+ mboxes = <&ipcc 0>, <&ipcc 1>;
+ };